Regulation of membrane trafficking by a novel Cdc42-related protein in Caenorhabditis elegans epithelial cells

Rho GTPases are mainly known for their implication in cytoskeleton remodeling. They have also been recently shown to regulate various aspects of membrane trafficking. Here, we report the identification and the characterization of a novel Caenorhabditis elegans Cdc42-related protein, CRP-1, that shows atypical enzymatic characteristics in vitro. Expression in mouse fibroblasts revealed that, in contrast with CDC-42, CRP-1 was unable to reorganize the actin cytoskeleton and mainly localized to trans-Golgi network and recycling endosomes. This subcellular localization, as well as its expression profile restricted to a subset of epithelial-like cells in C. elegans, suggested a potential function for this protein in polarized membrane trafficking. Consistent with this hypothesis, alteration of CRP-1 expression affected the apical trafficking of CHE-14 in vulval and rectal epithelial cells and sphingolipids (C(6)-NBD-ceramide) uptake and/or trafficking in intestinal cells. However, it did not affect basolateral trafficking of myotactin in the pharynx and the targeting of IFB-2 and AJM-1, two cytosolic apical markers of intestine epithelial cells. Hence, our data demonstrate a function for CRP-1 in the regulation of membrane trafficking in a subset of cells with epithelial characteristics.

Relations between health-related quality of life and well-being: the gerontologist's new clothes?

Is the recent construct of health-related quality of life (HQL) distinct from what gerontologists have long referred to as "well-being" or "life satisfaction?" We addressed this question using data from men in the VA Normative Aging Study to examine relations among twelve scales assessing HQL and seven scales of well-being (WB). We hypothesized that these two constructs would be distinct factorially, and that the derived factors would have different correlates. Correlations between scales of HQL and WB were moderate. When the nineteen scales were factored, four factors were extracted with HQL and WB scales generally loading on separate factors. The factors had distinct patterns of relations with general quality of life, personality, and the presence of a health problem, controlling for sociodemographics. These results suggest that HQL is distinct from the older construct of well-being. Although the two constructs are conceptually related, there is only a moderate amount of statistical overlap between them. Gerontologists should readily adopt health-related quality of life, which maintains continuity with such classics as well-being. This new construct, although needing slight alterations to broaden its assessment of well-being and life satisfaction, holds promise as more than an accessory in the study of health and well-being among older persons.

Employment and health among older bereaved men in the normative aging study: one year and three years following a bereavement event

Research has indicated that the negative effects of bereavement on health among elderly men occur within the first six to twelve months following a bereavement event while other studies indicate that the death of a loved one can have long-term effects on social functioning and mental health (Arbuckle & DeVries, 1995; Vinick, 1983a). However, employment has been found to buffer the strain produced by stressful life events. The purpose of this study was to examine the differential effects of employment on physical and mental health between elderly men bereaved for one year and elderly men bereaved for two to three years. We selected two groups of men from the Normative Aging Study: those bereaved within the past year (N = 248) and those bereaved from two to three years (N = 262). Ordinary least squares multiple regression analyses examined the direct effect of employment, controlling for age, education, income, marital status, and stress, on physical and mental health among the two groups of men. Although there were no significant differences between the two groups of men, the results from the separate analyses indicated that employment had a direct positive effect on physical health among those bereaved for one year and those bereaved from two to three years, but no significant effects were observed on mental health. The results suggest that employment can benefit men soon after a bereavement event and also over a longer period of time, especially on physical health. Implications for clinical practice and future research are discussed.

Gonadal hormones modulate 5-hydroxytryptamine2A receptors: emphasis on the rat frontal cortex

The effect of short-term (Sprague-Dawley rats, two weeks) and long-term ovariectomy (Sprague-Dawley and Fischer rats, three months) on serotonin 5-hydroxytryptamine2A receptors in different regions of the brain and its possible correction with an 17 beta-estradiol treatment (10 micrograms, b.i.d., two weeks) were studied in comparison to intact rats. Saturation binding assays were performed using [3H]ketanserin to estimate 5-hydroxytryptamine2A receptor density and affinity in tissue homogenates of frontal cortex of Fischer rats and quantitative autoradiography was performed to evaluate receptor specific binding in frontoparietal cortex, nucleus accumbens, striatum and dorsal raphe nucleus of Fischer rats, and in frontal cortex of the two strains of rats. Messenger RNA levels of 5-hydroxytryptamine2A receptors were measured by in situ hybridization in frontal cortex of the two strains of rats. An overall decrease of 5-hydroxytryptamine2A receptor densities was found in all the brain regions of ovariectomized Fischer rats assayed, and this could be restored towards control levels by estradiol treatment. No change in the 5-hydroxytryptamine2A receptor affinity was measured in the frontal cortex. A similar pattern of changes was observed for the messenger RNA levels encoding the 5-hydroxytryptamine2A receptors and receptor density, suggesting the implication of a genomic mechanism. Experiments in Sprague-Dawley rats confirmed and extended the results obtained with Fischer rats. By analogy, in humans, this 5-hydroxytryptamine2A receptor modulation may underlie the mood and movement disorders associated with menopause.

Anterior pituitary hypoplasia and dwarfism in mice lacking the dopamine transporter

Deletion of the dopamine transporter (DAT) results in increased dopaminergic tone, anterior pituitary hypoplasia, dwarfism, and an inability to lactate. DAT elimination alters the spatial distribution and dramatically reduces the numbers of lactotrophs and somatotrophs in the pituitary. Despite having normal circulating levels of growth hormone and prolactin in blood, hypoplastic glands from DAT-/- mice fail to respond to secretagog stimulation. The effects of DAT deletion on pituitary function result from elevated DA levels that down-regulate the lactotroph D2 DA receptors and depress hypothalamic growth hormone-releasing hormone content. These results reveal an unexpected and important role or DA in the control of developmental events in the pituitary gland and assign a critical role for hypothalamic DA reuptake in regulating these events.

Ovariectomy and estradiol treatment affect the dopamine transporter and its gene expression in the rat brain

The impact of gonadal hormone withdrawal and estrogen therapy was investigated on the rat dopamine transporter (DAT). Short-term ovariectomized (ST-OVX, 2 weeks) and long-term ovariectomized (LT-OVX, 3 months) rats were treated or not with 17beta-estradiol (E2) for 2 weeks. DAT mRNA expression was measured by in situ hybridization in the substantia nigra pars compacta (SNc) for the nigrostriatal pathway and the ventral tegmental area (VTA) for the mesolimbic pathway whereas DAT levels were assessed by [3H]GBR-12935 autoradiography, respectively, in the striatum and the nucleus accumbens. Ovariectomy produced a time-dependent decrease of the DAT density in the striatum and the nucleus accumbens and the E2 treatment did not significantly restore these DAT levels. Neither ST-OVX nor E2 treatment of the ST-OVX animals altered the DAT mRNA expression in the SNc and the VTA. However, LT-OVX animals showed increased DAT mRNA levels in these regions. E2 treatment of LT-OVX animals partially restored DAT mRNA levels in the SNc and left these levels unchanged in the VTA. These opposite variations induced by OVX on the DAT density and their mRNA levels suggest the involvement of non-genomic mechanisms, such as post-transcriptional events and/or membrane effects. Altered neurotransmission following gonadal hormone withdrawal may contribute to CNS disorders occurring at menopause in predisposed women. Ovariectomized rats constitute a useful model to study the changes in neurotransmitters balance occurring after menopause.

The modulation of brain dopamine and GABAA receptors by estradiol: a clue for CNS changes occurring at menopause

1. Tardive dyskinesia is more important in postmenopausal women than men of comparable age and a peak of first episodes of schizophrenia is observed in postmenopausal women. The effect of ovariectomy (2 weeks or 3 months) in rats was investigated as a model of decreased gonadal function associated with menopause. 2. Frontal cortex D1 receptor density and affinity were similar in intact male compared to intact female rats and progressively decreased in density with time after ovariectomy, with no change of affinity. Striatal D1 and D2 receptors also decreased in density after ovariectomy for both receptor subtypes, with no change of affinity. Striatal D1 receptor density and affinity were similar in intact male and female rats, whereas the density of D2 receptors was higher in females. Treatment with estradiol for 2 weeks restored the D2 but not the D1 receptor changes. 3. In the substantia nigra pars reticulata, striatum, nucleus accumbens, and entopeduncular nucleus, a progressive increase in [3H]flunitrazepam specific binding associated with GABAA receptors was observed as a function of time following ovariectomy; this was corrected with estradiol treatment. In contrast, the opposite was observed for [3H] flunitrazepam binding in the globus pallidus, where ovariectomy decreased binding, which was corrected with estradiol replacement therapy. 4. Low prefrontal cortex dopamine activity with implications of D1 receptors in negative symptoms of schizophrenia is hypothesized. Furthermore, GABAergic overactivity in the internal globus pallidus-substantia nigra pars reticulata complex is hypothesized in tardive dyskinesia. 5. The present data suggest that gonadal hormone withdrawal by reducing brain dopamine receptors and producing an imbalance of GABAA receptors in the output pathways of the striatum may predispose to schizophrenia and dyskinesia.

Dopamine and GABAA receptor imbalance after ovariectomy in rats: model of menopause

A peak of first episodes of schizophrenia can occur in postmenopausal women. Furthermore, tardive dyskinesia is more common in postmenopausal women than in men of comparable age. This study investigated the effect of ovariectomy (2 weeks or 3 months) in rats as a model of decreased gonadal function associated with menopause. After ovariectomy, frontal cortex D1 receptors progressively decreased in density with no change of affinity over time. Striatal D1 and D2 receptors also had decreased density after ovariectomy with no change of affinity. In the substantia nigra pars reticulata, a progressive increase in [3H]flunitrazepam-specific binding associated with GABAA receptors was observed as a function of time following ovariectomy. It is hypothesized that low prefrontal cortex dopamine activity has implications in negative symptoms of schizophrenia and, furthermore, that GABAergic overactivity in the internal globus pallidus-substantia nigra pars reticulata complex plays a role in tardive dyskinesia. The present results suggest that, by reducing brain dopamine receptors and increasing GABAA receptors, gonadal hormone withdrawal may predispose to schizophrenia and dyskinesia.

Discrimination between putative bradykinin B2 receptor subtypes in guinea pig ileum smooth muscle membranes with a selective, iodinatable, bradykinin analogue

We have synthesized a potent, selective, radioiodinated bradykinin (BK) analogue with high specific radioactivity (1000-1500 Ci/mmol). The new tracer, 125I-[p-Phe5]BK, was prepared carrier-free from the corresponding nitro precursor, [p-NO2-Phe5]BK, via catalytic hydrogenation and halodediazotation. This peptide bound to guinea pig ileum membranes in a biphasic pattern, with a high affinity dissociation constant of 3 pM (Bmax = 22 fmol/mg of protein) and a low affinity dissociation constant of 192 pM (Bmax = 245 fmol/mg of protein). The kinetically determined Kd values were 2 pM and 910 pM, respectively. The properties of the new tracer and of the peptide analogues [p-iodo-Phe5]BK and [p-NO2-Phe5]BK were compared with those of [3,4-3H(N)] [2,3-prolyl]BK as label in both saturation and inhibition studies. The results indicated that [p-iodo-Phe5]BK possessed increased affinity for the high affinity site and decreased affinity for the low affinity site, relative to BK. In rat myometrial membranes, in contrast, [p-iodo-Phe5]BK failed to reveal a high affinity site and displayed reduced affinity for the low affinity site, compared with BK. The nitro precursor was a nonselective ligand with nanomolar affinity for all labeled binding sites in both membrane preparations. Measuring the influence of BK and its analogues on guanosine-5'-O-(3-[35S]thio)triphosphate binding to guinea pig ileum membranes, we showed that G proteins were separately activated via both binding sites, qualifying these sites as constituents of signal transduction pathways and, therefore, real membrane receptors. With the new tracer as label, the B2 receptor antagonists D-Arg0-[Hyp3,Thi5,D-Tic7,Oic8]BK and D-Arg0-[Hyp3,Thi5,8,D-Phe7]BK recognized both binding sites with very high affinity in guinea pig ileum membranes, classifying these sites as B2 receptors. The BK-induced contraction in guinea pig ileum is obviously mediated via the receptor with nanomolar affinity, but the physiological role of the high affinity receptor is still unknown.

Methylation in positions 1 and 7 of angiotensin II. A structure-activity relationship study

Six analogues of angiotensin II (Ang) were synthesized with modifications in positions 1 and 7. The study was undertaken in order to learn more about the influence of alkylations in positions 1 and 7 and their interdependence. Previous studies have shown that alpha, alpha-dimethylation of Gly (aminoisobutyric acid, Aib) in position 1 produces quite potent analogues, as does N-methylation of Gly (sarcosine). Combination of both C alpha- and N alpha-methylations to N-Me-Aib1, however, did not produce an affinity increase. Decyclisation of the Pro7-residue produced moderately active analogues with position 7 N-methylation and inactive analogues if the N-alkylation was suppressed. In order to investigate a possible stereochemical interdependence of positions 1 and 7, a group of peptides with combinations of position 1 and 7 alkylations were investigated. The following analogues were prepared: [Sar1,Aib7]Ang, [Sar1,Aib,Leu8]Ang, [Aib1,7,Leu8]Ang, [Aib1,7,Leu8]Ang, [N-Me-Aib1,Aib7]Ang, [N-Me-Aib1,Aib7,Leu8]Ang. They were synthesized by classical solid phase synthesis using the BOC-TFA-HF scheme. The biological properties of these peptides were assessed on the rabbit aorta preparation and their binding potencies were measured on bovine adrenal membranes. Both on agonistic and antagonistic [Leu8]Ang analogues single Aib substitutions in position 1 or 7 induced affinity reduction in both bioassays. Simultaneous Aib modifications in positions 1 and 7 induced more important affinity loss in a synergic manner in both bioassays and as well for agonists and antagonists. The N-Me-Aib1 modifications induce similar affinity loss with or without concomitant Aib7 modification.(ABSTRACT TRUNCATED AT 250 WORDS)

Construct validation of optimism and pessimism in older men: findings from the normative aging study

Validation of Scheier and Carver's (1985) Life Orientation Test (LOT) has identified associations between bipolar optimism and several external constructs. However, optimism and pessimism may be not bipolar, but rather separate constructs. Furthermore, these constructs may be indistinguishable from personality traits, such as neuroticism and extraversion. This study examined the associations of separate optimism and pessimism measures with self-reports of hassles, psychological symptoms, and illness severity, controlling for personality. Ss were 1,192 men from the Normative Aging Study. Findings suggest that optimism and pessimism are separate and that their relations to external criteria remain, although attenuated, when neuroticism and extraversion are controlled.

Construct validation of optimism and pessimism in older men: findings from the normative aging study

Validation of Scheier and Carver's (1985) Life Orientation Test (LOT) has identified associations between bipolar optimism and several external constructs. However, optimism and pessimism may be not bipolar, but rather separate constructs. Furthermore, these constructs may be indistinguishable from personality traits, such as neuroticism and extraversion. This study examined the associations of separate optimism and pessimism measures with self-reports of hassles, psychological symptoms, and illness severity, controlling for personality. Ss were 1,192 men from the Normative Aging Study. Findings suggest that optimism and pessimism are separate and that their relations to external criteria remain, although attenuated, when neuroticism and extraversion are controlled.

Change in social support after retirement: longitudinal findings from the Normative Aging Study

Although retirement is generally thought to lead to a decline in social support due to a loss of social contacts with coworkers, the evidence for this is at best contradictory. This longitudinal study examined change in social support among 1,311 men, participants in the Veterans Administration Normative Aging Study, over a 3-year period. In general, long-term retirees reported the least quantitative social support, and the continuing full-time workers the most; however, change in workforce status produced no apparent effect on quantitative support over the duration of this study. In general, qualitative support showed no retirement effects. We also examined more specific patterns of coworker friendship and again found a pattern similar to that of general quantitative support. The findings support our earlier suggestion of a distinction between retirement as a transition and retirement as a state, and also support the convoy model of social support in late life and the selectivity theory of developmental adaptation to aging.

Photoaffinity labeling of subtype 2 angiotensin receptor of human myometrium

Angiotensin II (AII) binding sites were characterized in human myometrium membrane preparations. The sites were saturable and of high affinity (Kd of 0.09 nM and Bmax of about 200 fmol/mg of protein). PD 123319 completely inhibited 125I-AII binding, with an IC50 of 30 nM, whereas L-158,809 (1 microM) had no significant effect on 125I-AII binding. These results indicate that human myometrium contains almost exclusively the AT2 receptor subtype. Association and dissociation studies performed with 125I-AII on human myometrium membranes revealed that AII had a very high affinity for AT2 receptors, with a Kd of 0.01 nM (association rate constant K1 = 1.056 x 10(12) mol-1 min-1; dissociation rate constant K2 = 0.003 min-1). The photoactivable AII analogue [Sar1, Val5, D-Phe8(N3)]AII displayed a high affinity for AT2 receptors (IC50 of 0.18 nM), but its radioiodinated form showed poor efficiency in photoaffinity labeling experiments. A newly synthesized photoactivatable analogue of AII, [Sar1, p-benzoyl-Phe8]AII, (AII-Bpa), also displayed a high affinity for AT2 receptors of human myometrium (IC50 of 0.3 nM). Photoaffinity labeling experiments were performed with 125I-AII-Bpa, and a high yield (70%) of covalent incorporation to human myometrium membranes was obtained upon photolysis. Covalently labeled receptors were solubilized, denatured, and subjected to polyacrylamide gel electrophoresis. Autoradiography of the polyacrylamide gel revealed a single band, of 68 kDa, and the labeling of this band was completely abolished in the presence of 1 microM PD 123319, indicating selective labeling of the AT2 receptor subtype. These results demonstrate that AII-Bpa is a very efficient tool for selective photoaffinity labeling of the AT2 receptor.

Sar1-p-benzoylphenylalanine-angiotensin, a new photoaffinity probe for selective labeling of the type 2 angiotensin receptor

Previous photoaffinity labeling of angiotensin II (Ang) receptors with azidophenylalanine containing Ang analogs produced high yield labeling of a 60 kDa protein on bovine adrenocortical membranes. This preparation is mostly enriched in the type 1 Ang receptor (AT1) and AT1 selective ligands (L158,809) totally prevented labeling, therefore confirming the AT1 nature of the labeled protein. Our attempt to photolabel the type 2 Ang receptor (AT2) of human myometrium with [Sar1,D-Phe(N3)8]Ang was unsuccessful, revealing a high degree of photolabeling selectivity. An Ang analog, [Sar1,Bpa8]Ang (or BpaAng) was prepared containing the photosensitive amino acid p-benzoylphenylalanine (Bpa). This compound was a specific but non-competitive Ang antagonist on rabbit aorta with a pA2 of 8.5. It displayed good binding affinities for bovine adrenocortical membranes (Kd = 6.5 nM), a predominantly AT1 preparation, and for human myometrium membranes (Kd = 0.39 nM), a predominantly AT2 preparation. Photolabeling experiments with iodinated BpaAng showed that AT1 was not covalently labeled whereas AT2 was covalently labeled with high yield. Labeling specificity was verified with the AT2-selective ligand PD123319 and with the AT1-selective antagonist L158,809. Our results indicate that 125I-BpaAng is exclusively labeling AT2 sites. This compound should be a useful tool for further biochemical characterization of the AT2 binding site.

Personality and aging: a study of the MMPI-2 among older men

We examined whether separate norms for older men are necessary for the revised Minnesota Multiphasic Personality Inventory (MMPI-2). Scores from 1,459 men in the Normative Aging Study (NAS) (age: M = 61.27, SD = 8.37) were contrasted with those from 1,138 men from the MMPI Restandardization Study (age: M = 41.71, SD = 15.32). Results showed that scores on the MMPI-2 validity, clinical, and content scales for the NAS men were highly similar to those from the MMPI-2 Restandardization sample. There were also few differences between the two groups at the item level. Within-sample analyses revealed some differences between age groups. However, the magnitudes of these differences were small and may represent the single or combined effects of cohort factors and age-related changes in physical health status rather than age-related changes in psychopathology per se. We concluded that special, age-related norms for the MMPI-2 are not needed for older men.

How stressful is retirement? Findings from the Normative Aging Study

The stressfulness of retirement both as a transitional event experienced during the past year and as a life stage was investigated. Transitional stress was assessed using a life events approach, and stage stress using a "hassles" approach. Respondents were 1,516 male participants in the Normative Aging Study, 45% of whom were retired. Among those retiring in the past year, respondents' own and spouse's retirement were rated the least stressful from a list of 31 possible events. Only 30% found retirement stressful. Retirement hassles were also less frequently reported and were rated less stressful than the work hassles of men still in the labor force. The only consistent predictors of both transitional and stage retirement stress were poor health and family finances; personality did not predict retirement stress.

Personality and aging: A study of the MMPI-2 among older men

We examined whether separate norms for older men are necessary for the revised Minnesota Multiphasic Personality Inventory (MMPI-2). Scores from 1,459 men in the Normative Aging Study (NAS) (age: M = 61.27, SD = 8.37) were contrasted with those from 1,138 men from the MMPI Restandardization Study (age: M = 41.71, SD = 15.32). Results showed that scores on the MMPI-2 validity, clinical, and content scales for the NAS men were highly similar to those from the MMPI-2 Restandardization sample. There were also few differences between the two groups at the item level. Within-sample analyses revealed some differences between age groups. However, the magnitudes of these differences were small and may represent the single or combined effects of cohort factors and age-related changes in physical health status rather than age-related changes in psychopathology per se. We concluded that special, age-related norms for the MMPI-2 are not needed for older men.

The MAC scale in a normal population: the meaning of "false positives"

The MAC scale has been very successful in identifying alcoholics and, in studies of clinical populations, is often considered a test for predisposition to alcoholism. MacAndrew, however, holds that the MAC scale assesses a more general personality trait characterized by sociability, boldness, rebelliousness and pleasure seeking. The present study examines the distribution of MAC scale scores in a normal population and tests for correlates of high MAC scores other than alcohol-related problems (e.g., arrest history). The sample consisted of 1,117 men, participants in the Normative Aging Study (mean age = 61.6). As expected, heavier drinkers and problem drinkers reported significantly higher MAC scale scores than did lighter and nonproblem drinkers. However, arrestees without drinking problems had MAC scale scores nearly identical to those of problem drinkers without arrest histories (23.19 and 23.42, respectively). Further, 36% of the sample without problem drinking or arrest histories had MAC scale scores of 24 or above, the clinical indicator of alcoholism, and more than 32% of these had scores above 27. In the entire sample, of the 152 men who had MAC scores above 27, 71% had no problems, either with arrest or drinking. Results are interpreted as supporting MacAndrew's interpretation of the meaning of the MAC scale as a general personality measure rather than a specific alcoholism instrument.

Personality and dental care utilization: findings from the VA longitudinal study

The personality traits of introversion/extraversion and neuroticism were investigated as determinants of the utilization of restorative dental care, controlling for socioeconomic status and restorative need. The VA Dental Longitudinal Study (DLS) provided information on the restorative treatment received by 593 healthy adult males during a 10-year period. Utilization of restorative services was measured by calculating the percentage of surfaces that needed and received treatment, as identified by the DLS examiners by clinical and radiographic examination. Oral examinations were initiated in 1969 with subsequent examinations occurring at approximately 3-year intervals. Personality measures for these individuals were obtained using the EPI-Q, a shortened form of the Eysenck Personality Inventory. A plot of neuroticism versus the utilization measure yielded a curvilinear relationship suggesting that participants seeking the most dental care scored moderately on the neuroticism scale while those scoring lowest and highest on this scale sought less treatment. In contrast, the introversion/extraversion scale showed no apparent relationship with dental care utilization. Results from the regression analysis suggest that dentition and socioeconomic status are strong determinants of utilization and that need for restorative treatment influences utilization.

Longitudinal findings from the Normative Aging Study: II. Do emotionality and extraversion predict symptom change?

We investigated the relationship between the personality traits of emotionality and extraversion and symptom-reporting, both cross-sectionally and longitudinally. The sample consisted of 1,034 men, initially screened for good health, who completed both the 16PF and at least two CMIs, (M = 5, range = 2-8) over an average period of 17 years (range = 2-25). Using a two-stage growth model, we obtained a predicted baseline and slope for each man for self-reported physical and psychological symptoms. Correlations revealed that emotionality was positively related to the numbers of both physical and psychological symptoms reported at baseline, while extraversion was negatively related. However, regression analyses including age and both personality variables indicated that only emotionality was associated with level of symptom-reporting. Longitudinal analyses revealed that emotionality was unrelated to physical symptom slopes and only weakly related to psychological slopes. We interpret these results as showing that, while personality and symptom-reporting are related cross-sectionally, personality does not predict changes in symptom reporting.

Differences in social support among retirees and workers: findings from the Normative Aging Study

Cross-sectional differences between retirees and workers in the importance of coworkers as a source of support, as well as in general quantitative support (social networks and frequency of interaction) and qualitative support (confidants and the perceived reliability of support) were examined. The sample consisted of 1,513 older men (mean age = 61), participants in the Normative Aging Study. Half (56%) were working, and the rest were retired. Slightly fewer retirees than workers reported coworker friends, especially among those who were long-term retirees or who did not work at all in retirement. Whereas similar findings were seen with quantitative support, workers and retirees reported nearly identical levels of qualitative support. However, retirees almost never discussed personal problems with former coworkers. The relevance of these findings for the convoy construct is discussed.

Differences in social support among retirees and workers: Findings from the Normative Aging Study

Cross-sectional differences between retirees and workers in the importance of coworkers as a source of support, as well as in general quantitative support (social networks and frequency of interaction) and qualitative support (confidants and the perceived reliability of support) were examined. The sample consisted of 1,513 older men (mean age = 61), participants in the Normative Aging Study. Half (56%) were working, and the rest were retired. Slightly fewer retirees than workers reported coworker friends, especially among those who were long-term retirees or who did not work at all in retirement. Whereas similar findings were seen with quantitative support, workers and retirees reported nearly identical levels of qualitative support. However, retirees almost never discussed personal problems with former coworkers. The relevance of these findings for the convoy construct is discussed.

An angiotensin with prolonged action and blood pressure--lowering properties

[Sar1,Phe(Br5)8] angiotensin II (Br5Ang II) is a specific, quasi-irreversible antagonist of angiotensin II (Ang II) in vitro. In vivo, this compound is a very potent, Ang II-specific antagonist with a very long duration of action against Ang II-induced blood pressure (BP) increases. In the "low-sodium" dog, this compound induces a prolonged BP reduction during and after intravenous infusion at doses comparable to cilazapril, a potent ACE inhibitor. The physicochemical and pharmacokinetic behavior of this peptide was therefore assessed to understand and interpret the prolonged antagonistic and antihypertensive activity of this peptide. Binding studies using beef adrenocortical membranes indicated specific binding of Br5Ang and related analogues to Ang II receptors with a Kd of 1.41 x 10(-9) M against iodinated [Sar1, D-Phe8]Ang II, a standard radioligand antagonist. Iodinated Br5AngII exhibited a very high degree of nonspecific binding to the membranes. It had an octanol-water partitioning coefficient of log P of + 0.903, a coefficient 84-fold higher than for [125I][Sar1, D-Phe8]Ang II. Association kinetics of [125I]Br5Ang II were similar to the standard ligand [125I] [Sar1, D-Phe8]Ang II, but the half-life of dissociation was four times higher (60 vs. 15 min at 20 degrees C). Molecular modeling indicates a practically identical conformational behavior of both peptides, Br5Ang II and [Sar1, D-Phe8]Ang II but with an expanded hydration shell over the Br5 residue. It is concluded that the prolonged duration of action is due to the increased hydrophobicity of the peptide, which leads to a slow dissociation from the Ang II receptor.(ABSTRACT TRUNCATED AT 250 WORDS)

An angiotensin II antagonist with strongly prolonged action

A highly hydrophobic analogue of angiotensin II (AT), [Sar1,(2',3',4',5',6'-Br5)Phe8]AT exhibited strong and persistent specific antagonism against AT, both in vitro and in vivo. This peptide exhibited 32% of the binding affinity of [Sar1]AT towards membranes of bovine adrenal cortex, it was a specific AT antagonist of irreversible character on smooth muscle assays, and it also suppressed for over 120 min at 7.10(-8) M/kg the blood pressure response towards AT in the rat blood pressure assay. This compound harbours therefore the potential of a new class of AT-specific antihypotensive drugs.

Does emotionality predict stress? Findings from the normative aging study

Investigated whether emotionality, assessed in 1975, predicted the reporting of both objective stress (life events) and subjective stress (hassles) 10 years later, and how emotionality affected the relation between both objective and subjective stress and mental health. The sample consisted of 1,159 older men, participants in the Normative Aging Study. Path analysis revealed that the reporting of stress was confounded with personality: Individuals higher in emotionality reported both more life events and more hassles. Furthermore, individuals higher in emotionality exhibited slightly higher levels of symptoms under stress than did individuals lower in emotionality. Nonetheless, both stress measures contributed independent variance to the prediction of psychological symptoms, even controlling for prior levels of emotionality. Implications for the assessment of stress are discussed.

Longitudinal findings from the normative aging study: I. Does mental health change with age?

Longitudinal changes in self-reported symptoms were investigated using the Cornell Medical Index (CMI) in a sample of 2,041 men. The average man completed 5 CMIs (range = 2-8) over 17 (range = 2-25) years. Using a two-stage growth model, we first regressed symptoms against time on study for each man. The average slope of physical symptoms showed a moderate increase over time, but the average slope of psychological symptoms showed little change. Next, individual differences in change were examined using age at entry as an explanatory variable. Age accounted for 50% of the variance in physical symptoms at entry and 7% of the variance in slopes, but explained neither baseline level nor change in psychological symptoms. Rather, a U-shaped curve described the relation between age and psychological symptom change. These results, in concert with a developmental perspective, may help reconcile conflicting findings on aging and mental health.

Does emotionality predict stress? Findings from the Normative Aging Study

Investigated whether emotionality, assessed in 1975, predicted the reporting of both objective stress (life events) and subjective stress (hassles) 10 years later, and how emotionality affected the relation between both objective and subjective stress and mental health. The sample consisted of 1,159 older men, participants in the Normative Aging Study. Path analysis revealed that the reporting of stress was confounded with personality: Individuals higher in emotionality reported both more life events and more hassles. Furthermore, individuals higher in emotionality exhibited slightly higher levels of symptoms under stress than did individuals lower in emotionality. Nonetheless, both stress measures contributed independent variance to the prediction of psychological symptoms, even controlling for prior levels of emotionality. Implications for the assessment of stress are discussed.

Orderly endings: do men know when they will retire?

In order to describe the subjective (as opposed to the statistical) predictability of the retirement event, this study examined the timing of men's retirement relative to their own expectations. On-time and off-time retirements were assessed in a panel of older workers, participants in the VA Normative Aging Study, who were surveyed about work and retirement in 1978, 1981, and 1984. Over spans of two years, 66 percent of workers accurately predicted their eventual date of retirement (+/- 1 year), and 40 percent were exact to within three months. However, approximately one-third of workers did not accurately foresee their date of retirement, having either unfulfilled plans or unanticipated retirements. From a life course perspective, we interpret retirement as an orderly event when two-thirds of a sample can retire as planned. From a practical perspective (e.g., an interest in program development or research design), retirement is not orderly enough when one-third of exits are unscheduled.

Mental health differences among retirees and workers: findings from the Normative Aging Study

Researchers during the past decade have found little effect of retirement on physical health. However, retirement entails a number of losses, and its effect on mental health, as measured by the prevalence of psychological symptoms, is unclear. We examined psychological symptoms in a sample of 1,513 older men, participants in the Normative Aging Study, using the SCL-90-R (Derogatis, 1983). Analyses of variance indicated that retirees reported more psychological symptoms than did workers, even after controlling for physical health status. Exploratory analyses examining the circumstances of retirement found no effects for length of retirement or part-time employment, but did find effects for the timing of retirement. Both early and late retirees reported more psychological symptoms. Late workers (aged 66 and older) reported the fewest symptoms. Reasons for these findings are discussed.

Mental health differences among retirees and workers: Findings from the normative aging study

Researchers during the past decade have found little effect of retirement on physical health. However, retirement entails a number of losses, and its effect on mental health, as measured by the prevalence of psychological symptoms, is unclear. We examined psychological symptoms in a sample of 1,513 older men, participants in the Normative Aging Study, using the SCL-90-R (Derogatis, 1983). Analyses of variance indicated that retirees reported more psychological symptoms than did workers, even after controlling for physical health status. Exploratory analyses examining the circumstances of retirement found no effects for length of retirement or part-time employment, but did find effects for the timing of retirement. Both early and late retirees reported more psychological symptoms. Late workers (aged 66 and older) reported the fewest symptoms. Reasons for these findings are discussed.

An empirical test for phases of retirement: findings from the Normative Aging Study

Although gerontologists have shown considerable interest in describing possible phases of retirement, the temporal course of retirement experience remains largely unspecified. This study of 293 male retirees from the Normative Aging Study used cross-sectional data to compare levels of life satisfaction and lesiure activities across 6-month time intervals within the first 3 years after retirement. Regression models were used to test the hypothesis that men retired 0 to 6 months differed from men retired for longer periods. Findings showed that, compared with these recent retirees, men retired 13 to 18 months had lower levels of overall life satisfaction and self-perceived involvement in physical activities. Analyses of the constituents of life satisfaction showed greater optimism and future orientation among recent retirees and a comparative deficit at 13 to 18 months. These findings support an interpretation that the immediate postretirement period is marked by more enthusiasm and that some degree of temporary letdown or dysphoria is likely during the second year of retirement.

Change in blood pressure and total cholesterol with retirement

This study examines change in systolic blood pressure, diastolic blood pressure, and total serum cholesterol over a three-year span in two groups of men aged 55-74 years at follow-up: 1) 262 men who were working at baseline but retired at follow-up, and 2) 409 age peers who remained employed at both measurement times. Measures were obtained from medical examinations conducted since the early 1970s as part of the prospective Veterans Administration Normative Aging Study in Boston. Regression analyses showed an average increase of 3.44 mmHg in systolic blood pressure, 1.62 mmHg in diastolic blood pressure, and 5.56 mg/dl in cholesterol for retirees compared with workers. The relative increases in the blood pressure variables were statistically significant. However, a logistic regression analysis did not show a greater incidence of hypertension among retirees compared with workers. The odds ratio, standardized for baseline blood pressure, body mass index, and age, was 0.90 (95 per cent confidence interval 0.56-1.45). Among retirees only, analyses of covariance showed that levels of blood pressure and cholesterol were comparable from one six-month interval to the next in the three years preceding and following retirement. Overall, the effects of retirement were not of sufficient magnitude to conclude that retirement had a clinically significant impact on blood pressure or cholesterol.

Social contexts and motives for drinking in men

Factor analysis identified nine distinct contextual-motivational factors for drinking in 1517 healthy men. These factors were significant predictors of level of alcohol consumption and discriminated subjects reporting drinking problems from those reporting no problems.

The effect of retirement on physical health

This prospective study compared pre- to post-retirement changes in physical health among male retirees with changes among age peers who continued to work. The 229 retirees and 409 workers aged 55-73 at follow-up were all participants in the Veterans Administration Normative Aging Study. Physical health at baseline and follow-up (three to four years apart) was rated on a four-point scale according to the findings of medical examinations. Although physical health declined generally over time, regression analyses showed no significant difference between eventual retirees and continuing workers on health change, after controlling for age and excluding men who retired due to illness or disability. Among retirees alone, pre- to post-retirement health change was also not significantly associated with several circumstances which purportedly make the retirement transition more stressful, such as mandatory retirement or retirement to a reduced standard of living. The results of this study of physical health, which corroborate those of other studies based on self-reported health measures and mortality data, support the conclusion that the event of retirement does not influence the risk of health deterioration.

Smoking cessation in a prospective study of healthy adult males: effects of age, time period, and amount smoked

The present study examined effects on smoking cessation of three variables-chronological age, time period, and amount smoked-in 637 healthy male smokers aged 22-69 at baseline. Subjects were followed from 1962-1975 using life table procedures. Age was not significantly related to quitting rates (p = .150). The amount smoked effect approached significance (p = .096) with rates of quitting progressively lower at higher consumption levels. Powerful time-period effects were found (p = .008). Incidence rates of quitting increased from 1962-1970, after which a marked decline occurred. (Am J Public Health 1983; 73:446-450.)

The relationship of tar content to decline in pulmonary function in cigarette smokers

The impact of the tar content of cigarettes on pulmonary function was examined in 1,355 men. These men represented 383 current cigarette smokers, 555 former cigarette smokers, and 417 never smokers enrolled in longitudinal study of aging. Current smokers' cigarette exposure was estimated by the number of cigarettes smoked per day and tar content per cigarette. spirometry was performed twice on all subjects at a 5-yr interval. A multiple regression analysis indicated that tar content did not significantly influence baseline levels of forced vital capacity (FVC) or forced expiratory volume in one second (FEV1), after controlling for age, height, and number of cigarettes smoked. Similarly, tar content did not significantly influence follow-up levels of FVC or FEV1, after controlling for age, height, number of cigarettes, and baseline pulmonary function. These data suggest that low tar cigarettes may not protect smokers from an increased rate of decline in pulmonary function.

The effect of occupational exposure on pulmonary function: a longitudinal evaluation of fire fighters and nonfire fighters

To examine the chronic effect of fire fighting on pulmonary function, we undertook a longitudinal analysis of 168 fire fighters and 1,474 nonfire fighters enrolled in a study of normal aging. Spirometric measurements (FVC and FEV1) were obtained on all subjects over a 5-yr intake period (1963 to 1968) and these subjects were reexamined 5 yr later (1968 to 1973). Questionnaire information about smoking habits, respiratory symptoms, and illness was also obtained. Fire fighters had a greater loss of pulmonary function (FVC and FEV1) than nonfire fighters (p = 0.007 and p = 0.054). This occupational effect could not be explained by differences in age, height, smoking status, or initial level of pulmonary function between the two occupational groups. Although respiratory symptoms were greater among current cigarette smokers, they were not significantly different between either occupational group. However, fire fighters generally reported more symptoms when smoking was controlled for. These results confirm earlier reports of a chronic effect of fire fighting on pulmonary function and suggest an association of this occupational with increased respiratory symptoms and disease independent of cigarette smoke.

Retrospective analysis in smoking cessation research

The use of retrospective data in smoking research represents possible sources of bias resulting from: (1) baseline incomparability of current, former, and non-smokers, (2) instability of parameters under investigation, and (3) difficulties in recall. A self-report measure of smoking motives was employed in a longitudinal design to examine bias associated with retrospective data analysis. Thirty-six pairs of former smokers and recidivists (smokers who had tried to quit) were matched on age and amount smoked. Although initial responses for both groups were comparable, former smokers were significantly higher on smoking motive factors after quitting compared to recidivists who stayed essentially the same. The findings suggest that mean differences in smoking motives between recidivists and former smokers assessed cross-sectionally may not accurately reflect the magnitude of the differences that existed when both groups were smoking.

Longitudinal effect of age and smoking cessation on pulmonary function

Although it is well known that pulmonary function declines with age and that this decline is accelerated by cigarette smoking, it is not as clear what effect smoking cessation has on pulmonary function. The Normative Aging Study, a longitudinal aging study of 2,280 men, has assessed this question. Longitudinal data on smoking and pulmonary function were available on 850 healthy men. Of 452 who smoked at entry to the study, 98 quit during a 5-yr period. There were no significant differences between current and ex-smokers in FVC (p = 0.12) and FEV1 (p = 0.66) at entry into the study. However, significant differences were observed during the 5-yr period in FVC and FEV1 decline between current, former, and never smokers, after adjusting for age and initial pulmonary function. The decrease in FVC for men who quit smoking was significantly less than that for current smokers (p = 0.02). Similarly, FEV1 for former smokers decreased significantly less than for current smokers (p less than 0.001). When multiple regression was performed among former smokers, no significant effects of years since quitting on rate of decrease in FVC and FEV1 were seen. This study suggested a definite and rapid beneficial effect of smoking cessation.

Relationship between cigarette smoking, chest size and body size in health-screened adult males

Previous investigations have shown that chest dimensions and pulmonary function are positively correlated in healthy individuals. It is not known, however, whether the pulmonary effects of cigarette smoking may modify chest size during adulthood. The present study used cross-sectional data from 1557 healthy male participants in the Normative Aging Study of the Veterans Administration Outpatient Clinic, Boston. Because elastic recoil of the lung is decreased in cigarette smokers, we hypothesized that chest circumference would increase while chest expandability would decrease in these individuals. Preliminary analyses showed that smokers differed from non-smokers and former smokers in age, weight and fatness. For this reason, associations of chest dimensions with smoking status were evaluated after statistical correction for age and body size. With men of all ages grouped, chest expansion of smokers was significantly lower than non-smokers, but their chest size and shape were similar. When covariance analyses were performed separately for men under 50 and over 50 years, older smokers were characterized by slightly larger chests than non-smokers or former smokers, though there was no difference among younger men. Results of this study indicate that external chest dimensions of cigarette smokers reflect the pulmonary changes they experience, and demonstrate that a portion of the increased variability in chest measurements seen in older individuals is attributable to cigarette smoking.

Predictors of weight change following smoking cessation

Smoking behavior and weight change over a 5-year period were studied in 1,749 adult males of the Normative Aging Study. While men who quit smoking generally gained more weight than those in other smoking categories, 36% either lost weight or maintained the same weight after quitting. The major research focus was to predict the direction of weight change after smoking cessation. Among the characteristics most related to weight gain after quitting were heavier tar consumption, younger age, and leanness of body build. Conversely, traits related to weight loss were lighter smoking, older age, and stoutness of build.

Cigarette smoking, aging, and decline in pulmonary function: A longitudinal study

Three serial spirometric determinations of forced vital capacity (FVC) and forced expiratory volume in 1 sec (FEV1.0) were performed during a 10-yr period for 268 adult male cigarette smokers, 181 quitters, and 254 who had never smoked. Smokers were further divided into high- and low-tar consumption groups. Spirometric data were analyzed by repeated measures analyses of variance using time (aging) and smoking status as independent variables and age as a covariate. Results indicated that FVC and FEV1.0 were relatd to smoking status. For all age groups, nonsmokers performed best on spirometry, while current smokers performed worst. The decline in FEV1.0 over time was greatest in current smokers, especially the high-tar group. Loss of FVC over time was not influenced by smoking status.

Concurrent change in planned and preferred age for retirement

Studies of older workers' readiness to retire have reported a growing trend toward plans or expectations for earlier retirement. At the same time, other studies have shown that as workers age they prefer progressively later ages for retirement. To clarify the relationship between planned and preferred age for retirement, concurrent trends in the two measures for a single sample of male workers were compared. At two sampling times 10 years apart, a panel of 912 workers (aged 45 to 74 at T2) was asked at what age they planned to retire and at what age they preferred to retire. The pattern of joint change in these two measures showed a dynamic relationship between them. Even though panel members generally preferred to retire sooner than they planned to, preferences were revised (toward later ages) over time and tended to converge with the planned age for withdrawal from work.